Photos: Skygazers wowed by transit of Venus

The rarest of astronomical phenomena
A Hindu Sadhu using protective eyewear observes the transit of Venus across the sun on June 6 in Guwahati, India.

Skygazers around the globe directed their telescopes and viewing glasses towards the sun to watch the rare planetary event. The latest transit, which took place on June 5 or June 6 (depending on your location), took place eight years after the previous transit on June 8, 2004. The next pair of transits will not occur until the year 2117 and 2125.

Venus transits occur on a repeating 243-year pattern in which two transit events occur eight years apart, with each pair being separated by long gaps of 105.5 and 121.5 years.

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Photo:SDO/NASA/Getty Images

Transits guide scientific advancements

In this ultra high-definition image captured by NASA's Solar Dynamics Observatory, Venus passes by the broiling, chaotic surface of the sun.

First observed through a telescope in 1639, the Venus transits helped early astronomers calculate the size of the solar system, and more specifically, it helped them estimate the distance between the sun and the Earth. Contemporary astronomers studied the 2012 transit in hopes of refining techniques used in the search for exoplanets.

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Photo:Manan Vatsyayana/AFP/Getty Images

Planetary silhouette
Venus, the black dot in the upper left corner of the sun, is seen in transit across the sun over the skies of New Delhi. This year's transit was visible from North America in the evening of June 5 and in eastern Asia and Australia in the early morning of June 6.